In accordance with the invention, thin bodies of plastic, such as sheets or strands, with substantially different thermal coefficients of expansion are laminated together to make plastic bodies which move in response to heat. The movable plastic bodies can be secured to a suitable base to make a variety...http://www.google.es/patents/US6966812?utm_source=gb-gplus-sharePatente US6966812 - Thermally movable plastic devices and toys
